Recently, as the interest in stereoscopic image services is growing, devices for providing stereoscopic images continue to be developed. Among the schemes for implementing such stereoscopic images is a stereoscopic scheme.
A basic principle of the stereoscopic image is that arranged images are separately input such that they are perpendicular to the left and right eyes of a person (or a user) and the images separately input to the left and right eyes are combined in the user's brain to generate a stereoscopic image. In this case, the arrangement of the images such that they are perpendicular means that the respective images do not interfere with each other.
Methods for preventing interference include a polarization scheme, a time-sequential scheme, and a spectral scheme.
First, the polarization scheme refers to separating respective images by using a polarization filter. Namely, the polarization filter perpendicular to an image for the left eye and an image for the right eye is employed to make different images filtered by the polarization filter input to the left and right visual fields. The time-division scheme refers to alternately displaying left and right images and active glasses worn by the user is synchronized with the alternately displayed images to thus separate the respective images. Namely, when the images are alternately displayed, the shutter of the synchronized active glasses opens only the visual field to which a corresponding image is to be input and blocks the other visual field to separately input the left and right images.
Meanwhile, the spectral scheme refers to projecting left and right images through a spectral filter having a spectrum band in which RGB spectrums do not overlap with each other. With respect to the thusly projected left and right images, the user wears passive glasses including a spectral filter passing through only a spectral area set for the left and right images, thus separately receiving the left and right images.
However, there are various 3D modes for the 3D image signals input to perform the foregoing related art 3D image implementing method, and failure of identifying 3D modes would lead to failure of implementation of 3D images.
In particular, in case of a 3D TV (three-dimensional television) displaying 3D images, unless the 3D modes are properly identified and formatted for a display output appropriately, 3D images cannot be properly displayed. Thus, in the case of the 3D TV, a 3D mode of an input 3D image signal is required to be confirmed and 3D image data is required to be formatted accordingly. However, a method enabling a 3D TV to confirm a 3D mode of an input 3D image signal and form a 3D image according to the corresponding mode has not been implemented yet.
Thus, without knowledge of such a situation, the user may fail to properly enjoy viewing of 3D images due to improper 3D image formatting. Also, in order to recognize and set a mode that is appropriate for the 3D mode applied to the 3D image signal, users are faced with inconveniences.